As temperatures cool and winter annual weeds begin to germinate, one of the most important investments that turfgrass professionals and landscape managers can make is a fall preemergent application. Annual bluegrass, chickweed, henbit, and bittercress are a few of the common weeds starting to emerge at this time. However, a well-timed preemergent to close out the growing season can establish a protective barrier, preventing these winter annuals from germinating and allowing you to focus on other areas in your managed spaces.
Two Quali-Pro tools for fall preemergent programs are Prodoxaben and Flumioxazin G. Both provide broad-spectrum broadleaf and grassy weed prevention and each offers advantages that allow professionals to build programs based on site needs, target species, and resistance management goals.
Prodoxaben: Two active ingredients with long-term residual control
Prodoxaben combines two proven active ingredients, prodiamine (HRAC Group 3) and isoxaben (HRAC Group 21) to deliver broad-spectrum preemergent control of more than 150 grassy and broadleaf weeds with a single application. Available in both Suspension Concentrate (SC) and Granular (G) formulations, Prodoxaben offers flexibility across a wide range of turfgrass, landscape, and native area applications.
The value of Prodoxaben lies in its residual longevity. Independent research has demonstrated up to 97% control of large crabgrass for at least 133 days with a single 2.0 fl oz/1000 ft2 application and greater than 75% winter broadleaf control for up to 63 days, outperforming comparable combination pre-emergents that failed to maintain control beyond 42 days. Depending on the rate and environmental conditions, a single application of Prodoxaben can provide up to 8 months of residual control, making it an excellent foundation for any weed control program.
Trial conducted by T. Teuton, Ph.D; Southeastern Turfgrass Research Center, Anthony, FL. Treatments applied on Oct 8, 2021. Irrigation applied within 2 hours post-application.
Flumishield G: A new granular option for fall weed prevention
The addition of Flumishield G to the Quali-Pro portfolio offers additional flexibility for a previously narrow-use profile preemergent active ingredient. By bringing flumioxazin (HRAC Group 14) to a granular form, this broad-spectrum preemergent has a new, expanded use on both warm- and cool-season turfgrass, regardless of dormancy status. Flumishield G is labeled for established Kentucky bluegrass, perennial ryegrass, tall fescue, fine fescue, chewings fescue, bermudagrass, zoysiagrass, St. Augustinegrass, buffalograss and seashore paspalum, for flexibility across different turfgrass systems. It is also an excellent option for landscape beds and native areas.
Flumishield G delivers a Group 14 mode of action, providing turf and landscape managers with a valuable rotational option for resistance management. As a PPO inhibitor, flumioxazin offers a different mechanism than many root-inhibiting preemergent herbicides, helping diversify weed control programs while maintaining broad-spectrum residual control. In an independent study, Flumishield G provided up to 100% control of Poa annua in an area suspected of having Group 3-resistant populations, observed through a breakthrough of the weed in the prodiamine-treated plots.
Trial conducted by J. Brosnan, Ph.D; University of Tennessee. Hybrid bermudagrass 'Tifway' fairway. Treatments applied on September 15, 2025. Measurable rainfall occurred 6 DAA. Resistance to HRAC 3 was suspected at this site.
Flumishield G also offers research-proven control of difficult winter broadleaf annuals. In another independent trial, Flumishield G had up to 90% control of henbit throughout winter with the longest residual control of all other products tested the following spring.
Trial conducted by M. Harrell, PhD; Southeastern Turfgrass Research Center, Lexington, KY. Treatments applied on September 12, 2025. Irrigation applied within 2 hours post-application.
Final Thoughts for Fall
When applied in the fall ahead of winter annual weed germination, both Prodoxaben and Flumishield G serve as important tools in a proactive preemergence strategy. Prodoxaben delivers broad-spectrum, long-lasting control through two complementary active ingredients, while Flumishield G introduces a Group 14 preemergent rotational option for sustainable resistance management on warm- and cool-season turfgrasses, landscapes, and native areas. Whether you're managing turf, landscapes, nurseries, or native areas, fall is an ideal time to evaluate your preemergent program and prepare for long-term success.
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